Tension-governor for piano-players.



E. LUNDBERG.

TENSION GOVERNOR FOR PIANO PLAYERS.

APPLICATION FILED JULY 20. L915.

1,244,875. Patented Oct. 30,1917.

3 SHEETS-SHEET I- E. LUNDBERG.

TENSIDN GOVERNOR FOR PIANO PLAYERS.

APPLICATION FILED IULY 20.1915- Patented Oct. 30, 1917.

3 SHEETSSHEET 2 Inventor.-

Lundben E. LUNDBERG.

TENSION GOVERNOR FOR PIANO PLAYERS.

APPLICATION FILED JULY 20.1915.

as a? 55k 39 Patented Oct. 30, 1917 3 SHEETS-SHEET 3.

fiweuor: Znd/fiedlzazdey UNITED STATES PATENT OFFICE.

ENDFRED LUNDBERG, OF TORONTO, CANADA, ASSIGNOR TO THE OTTO HIGEL (30., LIMITED, OF TORONTO, ONTARIO, CANADA.

TENSION-GOVERNOR FOR PIANO-PLAYERS;

Specification of Letters Patent.

Patented Oct. 30, 1917'.

Application filed July 20, 1915. Serial No. 40,993.

To all whom it may concern:

Be it known that I, ENDFRED LUNDBERG, citizen of the United States, residing at Toronto, Canada, have invented certain new and useful Improvements in Tension Governors for Piano-Players, of which the following is a. specification.

.The present invention relates to automatic piano players and pertains more specifically to improved means for governing or regulating the air tension in the player action. 7

The principal object of the invention is to provide an improved form of governor for automatic piano players, such as is used to control the variation of the air tension in the player action.

The ordinary means of controlling the tension of the air is by a spring attached to a pneumatic which opposes the tension. The higher the tension is the more the pneumatic will .collapse, and by strengthening or weakening the tension of the spring, more or less a higher or lower tension of air is maintained in the player action. One of the inadequacies of this style of governor is that under sudden changes, or under heavy irregular pumping, the valve very often closes too far and thereby chokes the player action. This difiiculty is overcome in the present device by a small pneumatic located inside the governor pneumatic which acts upon a lever in such manner that the latter prevents the valve from closing too much .under sudden tension.- This small pneumatic is in direct communication with the high tension chamber while the space in'which the valve Works is under low or subdued tension. By using this opposing pneumatic far better results are obtained in soft playing. It balances the tension better and entirely overcomes the closing of the valve when the pedaling is irregular.

With these and other objects in view the invention consists in the construction and arrangement ofparts described in the following specification, illustrated in the accompanying drawings and pointed out in the appended claims.

In the drawings Figure 1 is a vertical transverse sectional View of an embodimentaof'lny invention as I it would appearwhenapplied to a piano;

Fig. 2 is a front elevation of the upper portion of the channelbo'ard showing the regulator. governor with the cover removed.

Fig. 3 is a transverse sectional view on line 3-3' of Fig. 2 looking toward the right,

or in the direction of the arrows, valve box 8 being omitted for convenience of illustration.

Fig. 4 is a similar view on line 4'l of Fig. 2 looking toward the right or in the direction of the arrows, and with valve box 8' likewise omitted, and also omitting parts 56-, 5'7 and 58- for clearness, but showing bracket 52 and spring 53 in dotted lines.

Fig. 5 is a: sectional elevation of the valve box viewed from the same: direction asv Fig.2.

Referring now to the drawings, 1 indicates the lower framework of the piano inwhich the operating parts of the player action hereinafter described are incased. The channelb'oard 2 carries on its rear side the pumping bellows 3, which are connected by means of the angle strap t and link 5, to the pedal P. The main storage or suction bellows 6 is mounted on the front of the channel board 2, while the expression'governor pneumatic 7, which forms the essential part of the invention, is located just above this bellows on the same side of the channel.

board. The valve box 8 is here shown secured to the channel board and communi cates with the upper player action through the pipe 9. The specific arrangement and location of these parts in respect to one other and to the channel board is not an essential feature as this may be varied for purposes of making the structure compact.

There are in each piano two valve boxes 8, one for treble and one for bass, and the upper player action is divided in the center so each controls a half of the player when the reroll lEWGI is set to rewind. Only one of these (that controlling the treble) will be described in the present specification and illustrated in the accompanying drawings.

Under normal conditions, when the instrument is being played, the air is drawn from the upper player action down the duct or pipe 9, entering the valve box 8 through the valve port 11, the valve 10 of which is open. The interior of the valve box 8 is subdivided by partitions into four separate chambers or compartments, whichwill, for convenience be referred to as 1, 11, III and IV; Chamber I'is constantly in open communication with chamber II through the valvele'ss opening 12, and thelatter is simimay in commanicationthmaghthe port 13 with the passage 14 passing down the channel board 2 to the expression governor 7. Chamber II also has communication with chamber IV through the port 15, the valve 16 of which is normally open. Chamber IV is in direct communication with the passage 17 of the channel board, through an elongated opening 18 of larger area than the port 18 leading from chamber II to the other channel board passage 14. Chamber III is always open to the atmosphere through the port 19 formed in its outer wall. pair of double puppet valves 20 and 21 are mounted in corresponding ports 22 and 23 formed in the lower partition between chamhers III and IV. The stems of these valves extend downwardly and are provided with buttons on their lower ends which rest upon operating diaphragms 24 and locatedin the lower wall of the chamber IV. Transverse horizontal passages 26 and 27 are formed in the partition between chambers III and IV. These passages at their inner ends communicate with the valved ports 22 and 23 and at their outer ends terminate in the metal nipples 28 and 29 respectively. The former of these is connected by means of a tube 30 with a second metal nipple 31 which in turn connects with a horizontal passage 32 formed in the lower wall of the valve box and in communication with a diaphragm chamber beneath a pneumatic diaphragm 33 upon which the lower end of the valve stemof the valve 16 rests. The other nipple 29 is connected similarly by means of a tube 34 with a second metal nipple 35 which in turn communicates with a horizontal passage 36 formed in the partition between the chambers I and III and which communicates with a diaphragm box beneath a pneumatic diaphragm 37 upon which the lower end of the valve stem of the valve 10 is attached. As previously stated the valves 20 and 21 are actuated by the pneumatic diaphragms 24 and 25. Air is supplied to the under sides of these diaphragms through passages 38 and 89 which lead to the metal nipples 40 and 41 located on the cover of the valve box. These nipples are suitably connected with controlling ports on the tracker bar (not shown).

The expression governor comprises a bellows pneumatic, one part 45 of which is permanently secured to the channel board 2 and is provided with the ports 46 and 47 communicating with the passages 14 and 17 respectively of the channel board. The outer movable part or cover 48 of the pneumatic is connected to the former by the flexible wall 49 and carries a metal arm or bracket 50 to the free end of which a coiled spring 51 is attached. This spring passes through an opening in a bracket 52 suitably supported from the edge of the channel board. A pin 53 passes through the bracket 52 and is adapted to engage between different coils of the spring 51 thus providing means of adjusting the tension of the latter. The action of the spring tends to keep the pneumatic normally distended in its open position. The port 46 previously described as'communicating between the interior, of the pneumatic and the passage 14 of the channel board are adapted to be normally open, hence no valve is provided for it. A flap valve 54 provided with a hinge 55 is secured to the inner face of the part 45 so as to close the port 47. A small wire spring 56 bears in a slot in the back of the flap valve and tends, when the pneumatic is collapsed to close the valve. To the back of the valve 54 is fastened a wooden arm or bar 57 the outer end of which rests upon a small projection 58 carried by the outer movable part 48. As the coiled spring 51 tends to normally hold the pneumatic distended it will be seen that the bar 57 hearing a ainst the piece 58 also tends to hold the flap valve 54 open against the action of the slight spring 56. In cases of strong irregular pumping however, the variable tension obtained by the above arrangement is not sufficiently delicate to obtain the best results, and in order to more successfully provide for this inefliciencv and prevent the valve 54 from completely closing under these cir-' cumstances the auxiliary pneumatic 59 is placed within the pneumatic 7 and so connected by the pivoted lever 60 to the flap valve 54 as to. augment the action of the coiled spring 51 on the latter. A duct or passage 61, formed in the channel board communicates with. the passage 17 and also with the interior of the auxiliary pneumatic 59 entering the latter at the port 62. The lever 60 is pivotally mounted at 63 in a bracket 64. One of its ends bears against a projecting lug 65 secured to the flap valve 54, while its other end bears in a similar manner against a projecting arm 66 carried on the free end of the movable part ofthe auxiliary pneumatic 59. As the pneumatic 59 collapses the arm 66 depresses the forward end of the lever 60 and at the same time the rear end is raised a corresponding distance and with it the flap valve 54.

The operation of the device is a follows:

Assuming the parts in their normal playing position, the exhaust is drawn from the upper player action down through the pipe 9, past the valve 10, which is open, into chamber II of the valve box. The valve 16 being open, chamber IV is in direct communication with chamber II, hence the greater amount of air will.- hedrawn through the port 18 down the passage 17. It will be understood that the port 13 leading from the chamber II is always open and hence a direct passage is established by way of the duct 14 to the governor regulator, The

passage 1-1 of the channel board terminates at the port 46 of the governor regulator 7, while the other passage 17 is continued on beyond the port 4L7 and connects with the main storage reservoir bellows 6. When the above operation takes place the exhaust air passes the governor regulator 7, which is held distended by the spring 51, without affecting it. When, however the governor cut-out is to be closed the following operations take place: Atmospheric air is admitted through the pipe a2, passes from the nipple 40 along the passage 38 inflating the pneumatic diaphragm 2st, which lifts the valve 20, allowing atmospheric air from chamber III to enter the passage 26 and pass by means of the outer pipe or tube 80 down into the passage 32 so as to inflate the diaphragm 33 and close the port 15, cutting off communication between chambers 11 and IV and consequently shutting off the port 18 as a means of direct communication between the upper action and the storage bellows 6. lVith this condition all the exhaust must be drawn down the passage 14 and hence through the governor pneumatic 7, passing in through the port 46 and out under the flap valve 54:. The tendency of the coiled spring 51 is to keep the governor pneumatic bellows from completely collapsing and consequently the valve 54 from entirely closing. Vhen the pumping is irregular and the exhaust excessive the auxiliary pneumatic 59 will be exhausted through the port 62 and passage way 61 to passage 17 and thence to the suction bellows 6. As 59 collapses it will move the lever 60 in such manner as has hereinbefore been described to aid in keeping the flap valve 54 from entirely closing.

Having thus described my invention,what I claim is 1. A tension governor comprising a main bellows pneumatic, a valve within said pneumatic and operatively connected with the movable side thereof, means adapted to normally hold said main bellows in a distended position and auxiliary means within said main bellows pneumatically operated, adapted to prevent closure of said valve, substantially as described.

2. A tension governor comprising a main bellows pneumatic, a controlling valve mounted therein, means carried on the movable part of said bellows pneumatic for opening said valve when the pneumatic is distended, means adapted to normally distend said pneumatic, and independent means pneun'iatically operated to prevent said valve from completely closing when said pneumatic is collapsed, said means comprising an auxiliary bellows and a two armed rocking lever having one arm adapted to cooperate with said valve and its other arm cooperating with a projection on said auxiliary bellows, substantially as described.

3. A tension governor comprising a main bellows pneumatic, a controlling valve mounted therein, means carried on the movable part of said bellows pneumatic, adapted to open said valve when said pneumatic is distended, means adapted to normally maintain said bellows in a distended position, and an auxiliary pneumatic bellows within said main bellows adapted to prevent said valve from closing when said main bellows is collapsed, substantially as described.

4. A tension governor comprising a main bellows pneumatic, spring means for nor mally maintaining said bellows distended, a controlling valve within said pneumatic, means cooperating with the movable part of said bellows adapted to hold said valve open when the bellows is distended, an auxiliary bellows pneumatic within said main bellows pneumatic and a two armed lever pivotally supported in said main bellows pneumatic, the two arms of said lever cooperating with said valve and the auxiliary pneumatic respectively, whereby when the latter is collapsed the former is prevented from entirely closing, substantially as described.

In testimony whereof, I have aflixed my signature in presence of two witnesses.

ENDFRED LUNDBERG.

Witnesses Geo. P. MAoKIE, N. R. TYNDALL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). 0. 

